its really how the car leaves with the weight and how fast you appy the power and your intentions for the pass.when the car is going 1.4/1.5 60fts a 3700+it should have a set of 28 spline and a posi.mine had the waves when i pulled them and my friend snapped his.at the time the cars were running 10s and 1.4 60fts and needed to hammer the 1st part of the track to run the number.now if your going to leave soft 1.7/1.8 60ft and appy the power later for your 10 sec pass the heavy duty stuff isnt needed.